1. Field of the Invention
The invention relates to swimming pool cleaning systems including rotary devices which eject jets of water along bottom surfaces of a swimming pool to agitate settled debris on the bottom of the swimming pool.
2. Description of the Prior Art
A great deal of effort is required to keep swimming pool surfaces clean. A variety of rotary devices (referred to as "cleaning heads") which eject high pressure water jets along bottom surfaces of swimming pools as water pressure to the cleaning heads is "cycled" are known. One such cleaning head is disclosed in U.S. Pat. No. 3,408,006. However, that device has a number of serious shortcomings. It is unduly complex and expensive. Furthermore, due to its complexity, it is less reliable than is desired for a swimming pool which requires a large number of cleaning heads. Another device, which is much less expensive than the device disclosed in U.S. Pat. No. 3,408,006, is described in my U.S. Pat. No. 4,200,230, incorporated therein by reference.
It is an object of the invention to provide an improved rotary swimming pool cleaning head device which is less complex both in construction and in operation than any previous rotary swimming pool cleaning device.
It is another object of the invention to provide a rotary swimming pool cleaning device which is less expensive than prior swimming pool cleaning heads.
A high degree of reliability is essential for any rotary swimming pool cleaning head utilized in large swimming pools, because the number of rotary devices required can be in excess of 15 for many large modern swimming pools. When such a large number of cleaning heads are required in a single pool, a high degree of reliability is required in order to avoid the inconvenience and expense of the frequent repairs which would be required if reliability of the cleaning heads were not high.
It is therefore another object of the invention to provide a low cost rotary cleaning device which is substantially more reliable than any previous rotary swimming pool cleaning head.